The improved actuator for rear-view mirrors is applicable to all types of industry, though it is particularly suited for large vehicles and even more specifically for use on large vehicles formed by the joining of several units, e.g. urban or suburban trams or trains in which it is necessary to watch the movement or access of people around the vehicle. It could also be used on buses, trucks, trolleybuses or other similar vehicles.
These rear view mirrors for large vehicles usually consist of a case which holds the mirror and is articulated at one side to a support which anchors it to the bodywork of the vehicle, while the other side can be folded against the bodywork in the habitual closed position until it is forced away from it by the actuator.
The action of the wind or of other factors may move the rear view mirror from the closed position to the open position at undesired moments. Such would be the case, for example, of the suction produced by the air when moving at speed through a tunnel, or of the rear view mirror being caught in the washing mechanism. For these reasons it seems advisable to be able to lock the case in position on the support.
The current state of technology applied to this type of rear-view mirror can be seen in Model ES U9500741, by the same applicants, which describes a movable rear-view mirror for large vehicles which can be turned automatically to place it parallel or perpendicular to the side of the vehicle, coinciding with the mirror's positions of closed or opened respectively, and which is made up of a case which holds the mirror, solidly articulated to a support fixed to the corresponding side of the vehicle. Furthermore the rear-view mirror has a rotating device fixed to the support, the axis of which is situated in the direction of the rotation axis of the case, which when actuated automatically causes the rear-view mirror to turn, opening or unfolding from the side of the vehicle; the device is turned in the opposite direction for the rear-view mirror to be once more folded against the side, the position normally adopted when the vehicle is in motion. It also has a fixing mechanism which ensures the said folded position of the mirror with respect to the support and the side of the vehicle to which it is attached. The system designed in this way is expensive to manufacture and the turning device used even more so.
The same applicants perfect and simplify the rear-view mirrors of the type described and make them more economical with the use of a linear pneumatic cylinder, of single or double action, and therefore submit for registration, with number U9902742, a rear-view mirror which includes a case which holds the mirror, and which is articulated to the support which can be fixed to the corresponding side of the vehicle, the case and the support being connected by a pneumatic cylinder, the action of which automatically causes the case to turn on its support, from a closed or folded position against the same to an unfolded position, which coincides with open, or vice versa, and the essential characteristic of which lies in the fact that one end of the pneumatic cylinder is anchored in an articulated manner to the case, while the free end of the piston is articulated to a projection on the support. The piston of the pneumatic cylinder has a prolongation directed towards the projection of the support upon which it is articulated. This arrangement achieves the swift and simple folding or unfolding of the rear view mirror although the locking mechanism continues to be pulled by means of an additional pneumatic cylinder.
At this stage of the technique it seems necessary to have a second pulling mechanism to force the locking mechanism, normally acting on a first locking element provided on the case carrying the mirror and part of the said locking mechanism against a second locking mechanism of said locking mechanism that is fixed to the support of the case, or vice versa. However, it is evident that this is expensive, as well as complex, because to the cost of a second cylinder must be added that of its valves, flow regulators or other elements necessary for its use.